mm: Convert __HAVE_ARCH_P..P_GET to the new style

Since __HAVE_ARCH_* style guards have been depricated in favour of
defining the function name onto itself, convert pxxp_get().
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/Y2EUEBlQXNgaJgoI@hirez.programming.kicks-ass.net

arch/powerpc/include/asm/nohash/32/pgtable.h

@@ -263,7 +263,7 @@ static inline pte_basic_t pte_update(struct mm_struct *mm, unsigned long addr, p
 }
 
 #ifdef CONFIG_PPC_16K_PAGES
-#define __HAVE_ARCH_PTEP_GET
+#define ptep_get ptep_get
 static inline pte_t ptep_get(pte_t *ptep)
 {
 	pte_basic_t val = READ_ONCE(ptep->pte);

include/linux/pgtable.h

@@ -291,14 +291,14 @@ static inline void ptep_clear(struct mm_struct *mm, unsigned long addr,
 	ptep_get_and_clear(mm, addr, ptep);
 }
 
-#ifndef __HAVE_ARCH_PTEP_GET
+#ifndef ptep_get
 static inline pte_t ptep_get(pte_t *ptep)
 {
 	return READ_ONCE(*ptep);
 }
 #endif
 
-#ifndef __HAVE_ARCH_PMDP_GET
+#ifndef pmdp_get
 static inline pmd_t pmdp_get(pmd_t *pmdp)
 {
 	return READ_ONCE(*pmdp);